From: Jonathan Wakely <jwakely@redhat.com>
Date: Mon, 19 Oct 2020 16:57:14 +0000 (+0100)
Subject: libstdc++: Use reserved name for C++20 attribute
X-Git-Tag: basepoints/gcc-12~4183
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=fc77484c4a4feb308c64371233cb65b280333953;p=thirdparty%2Fgcc.git

libstdc++: Use reserved name for C++20 attribute

Although the compiler supports the [[no_unique_address]] attribute, it's
not a reserved name prior to C++20, so we can't use it in std::tuple.
Use [[__no_unique_address__]] instead.

libstdc++-v3/ChangeLog:

	* include/std/tuple (_Head_base<Idx, Head, true>): Use reserved
	form of __no_unique_address__ attribute because
	no_unique_address is not reserved prior to C++20.
---

diff --git a/libstdc++-v3/include/std/tuple b/libstdc++-v3/include/std/tuple
index 11ad1991108e..adfd6213a149 100644
--- a/libstdc++-v3/include/std/tuple
+++ b/libstdc++-v3/include/std/tuple
@@ -122,7 +122,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       static constexpr const _Head&
       _M_head(const _Head_base& __b) noexcept { return __b._M_head_impl; }
 
-      [[no_unique_address]] _Head _M_head_impl;
+      [[__no_unique_address__]] _Head _M_head_impl;
     };
 #else
   template<size_t _Idx, typename _Head>